Critical speed, thresholds for vo2max and boundaries of the severe exercise intensity domain / Velocidad crítica, vo2máx y límites de el dominio de la intensidad del ejercicio severo / Velocidade crítica, vo2max e limites de o domínio de intensidade de exercício severo

ABSTRACT Introduction: The severe exercise intensity domain can be defined as the range of work rates or speeds over which VO2max can be elicited. Objectives: Our purpose was to determine if critical speed (running analog of critical power) identifies the lower boundary of the severe domain and to identify the upper boundary of the domain. Methods: Twenty-five individuals performed five running tests to exhaustion, each lasting > 2.5 min and < 16 min. The two-parameter speed vs time-to-exhaustion relationship generated values for critical speed and the three-parameter speed vs time-to-reach-VO2max relationship generated values for the threshold speed above which VO2max can be elicited. The relationships were solved to calculate the minimum time needed to elicit VO2max. Results: Critical speed (3.00 ± 0.38 m·s−1) and the threshold speed above which VO2max can be elicited (2.99 ± 0.37 m·s−1) were correlated (r = 0.83, p < 0.01) and did not differ (p = 0.70), confirming critical speed as the lower boundary of the severe domain. The minimum time needed to elicit VO2max (103 ± 7 s) and the associated highest speed at which VO2max can be elicited (4.98 ± 0.52 m·s−1) identified the upper boundary of the severe domain for these participants. Conclusion: The critical power concept, which requires no metabolic measurements, can be used to identify the lowest speed at which VO2max can be elicited. With addition of metabolic measurements, mathematical modeling can also identify the highest speed and shortest exercise duration at which VO2max can be elicited. Evidence Level I; Validating cohort study with good reference standards.

RESUMEN Introducción: El dominio de la intensidad del ejercicio severo se puede definir como el rango de ritmos o velocidades de trabajo sobre las que se puede obtener el VO2max. Objetivos: Nuestro propósito fue determinar si la velocidad crítica (funcionamiento analógico de potencia crítica) identifica el límite inferior del dominio severo e identificar el límite superior del dominio. Métodos: Veinticinco personas realizaron cinco pruebas de carrera hasta el agotamiento, cada una con una duración de > 2,5 min y <16 min. La relación de dos parámetros de velocidad frente a tiempo de agotamiento generó valores para la velocidad crítica y la relación de tres parámetros de velocidad frente a tiempo de alcance de VO2max generó valores para la velocidad umbral por encima del cual se puede obtener el VO2max. Las relaciones se resolvieron para calcular el tiempo mínimo necesario para obtener el VO2max. Resultados: La velocidad crítica (3,00 ± 0,38 m·s−1) y la velocidad umbral por encima de la cual se puede obtener el VO2max (2,99 ± 0,37 m·s−1) se correlacionaron (r = 0,83, p < 0,01) y no difirieron (p = 0,70), lo que confirma la velocidad crítica como el límite inferior del dominio severo. El tiempo mínimo necesario para obtener el VO2max (103 ± 7 s) y la velocidad más alta asociada a la que se puede obtener el VO2max (4,98 ± 0,52 m·s−1) identificaron el límite superior del dominio severo para estos participantes. Conclusión: El concepto de potencia crítica, que no requiere mediciones metabólicas, se puede utilizar para identificar la velocidad más baja a la que se puede obtener el VO2max. Con la adición de mediciones metabólicas, el modelado matemático también puede identificar la velocidad más alta y la duración más corta del ejercicio a la que se puede obtener VO2max. Nivel de Evidencia I; Estudio de cohortes con alto estándar de referencia.

RESUMO Introdução: O domínio de intensidade de exercício severo pode ser definido como a faixa de taxas de trabalho ou velocidades sobre as quais o VO2max pode ser obtido. Objetivos: Nosso propósito foi determinar se a velocidade crítica (execução analógica da potência crítica) identifica o limite inferior do domínio severo e identificar o limite superior do domínio. Métodos: Vinte e cinco indivíduos realizaram cinco testes de corrida até a exaustão, cada um com duração > 2,5 min e < 16 min. A relação velocidade de dois parâmetros contra tempo até a exaustão gerou valores para a velocidade crítica e a relação velocidade de três parâmetros contra tempo para alcançar o VO2max valores gerados para a velocidade limite acima da qual o VO2max pode ser obtido. As relações foram resolvidas para calcular o tempo mínimo necessário para eliciar o VO2max. Resultados: A velocidade crítica (3,00 ± 0,38 m·s−1) e a velocidade limite acima da qual o VO2max pode ser eliciado (2,99 ± 0,37 m·s−1) foram correlacionadas (r = 0,83, p < 0,01) e não diferiram (p = 0,70), confirmando a velocidade crítica como o limite inferior do domínio grave. O tempo mínimo necessário para eliciar o VO2max (103 ± 7 s) e a maior velocidade associada na qual o VO2max pode ser eliciado (4,98 ± 0,52 m·s−1) identificou o limite superior do domínio severo para esses participantes. Conclusão: O conceito de potência crítica, que não requer medidas metabólicas, pode ser usado para identificar a velocidade mais baixa em que o VO2max pode ser eliciado. Com a adição de medidas metabólicas, a modelagem matemática também pode identificar a velocidade mais alta e a duração mais curta do exercício em que o VO2max pode ser obtido. Nível de Evidência I; Estudo de coorte com alto padrão de referência.

Clinical effect of Guben-Huoxue decoction on chronic obstructive pulmonary disease / 国际中医中药杂志

Objective@#To explore the clinical effect of Guben-Huoxue decoction on chronic obstructive pulmonary disease (COPD) and its influence on patients'respiratory rehabilitation and quality of life.@*Methods@#A total 108 patients with COPD admitted to our hospital from May 2013 to January 2018 were selected as the research subjects. The patients were divided into control group and observation group by random number table grouping method, 54 in each group. All patients were given basic treatment such as oxygen inhalation, anti-infection, bronchiectasis, and correction of acidosis. The control group was treated with budesonide formoterol powder inhalation, while the observation group was treated with Guben-Huoxue decoction on the basis of the control group. The maximum ventilation volume per minute (MVV), forced vital capacity (FVC), forced expiratory volume in the first second (FEV1), forced expiratory volume in the second (FEV1%) were measured by pulmonary function meter. Adverse reactions were recorded.@*Results@#The difference of FVC, MVV, FEV1%, symptoms, activity ability, disease influence and comprehensive scores in the observation group were significantly greater than those in the control group (t values were 6.480, 13.679, 5.853, 3.743, 5.786, 5.309, 5.058, respectively, all Ps<0.05). The total effective rate (94.4%) in the observation group were significantly higher than those in the control group (79.6%); the total incidence of adverse reactions (9.3%) was significantly lower than that of the control group (25.9%), and the difference was statistically significant (P<0.05).@*Conclusions@#The Guben-Huoxue decoction can improve the clinical symptoms and pulmonary function of COPD patients, promote respiratory rehabilitation and improve the quality of life.

Clinical effect of Guben-Huoxue decoction on chronic obstructive pulmonary disease / 国际中医中药杂志

Objective To explore the clinical effect of Guben-Huoxue decoction on chronic obstructive pulmonary disease (COPD) and its influence on patients'respiratory rehabilitation and quality of life. Methods A total 108 patients with COPD admitted to our hospital from May 2013 to January 2018 were selected as the research subjects. The patients were divided into control group and observation group by random number table grouping method, 54 in each group. All patients were given basic treatment such as oxygen inhalation, anti-infection, bronchiectasis, and correction of acidosis. The control group was treated with budesonide formoterol powder inhalation, while the observation group was treated with Guben-Huoxue decoction on the basis of the control group. The maximum ventilation volume per minute (MVV), forced vital capacity (FVC), forced expiratory volume in the first second (FEV1), forced expiratory volume in the second (FEV1%) were measured by pulmonary function meter. Adverse reactions were recorded. Results The difference of FVC, MVV, FEV1%, symptoms, activity ability, disease influence and comprehensive scores in the observation group were significantly greater than those in the control group (t values were 6.480, 13.679, 5.853, 3.743, 5.786, 5.309, 5.058, respectively, all Ps<0.05). The total effective rate (94.4%) in the observation group were significantly higher than those in the control group (79.6%); the total incidence of adverse reactions (9.3%) was significantly lower than that of the control group (25.9%), and the difference was statistically significant (P<0.05). Conclusions The Guben-Huoxue decoction can improve the clinical symptoms and pulmonary function of COPD patients, promote respiratory rehabilitation and improve the quality of life.

Association between respiratory capacity, quality of life and cognitive function in elderly individuals / Associação entre capacidade respiratória, qualidade de vida e cognição em idosos

ABSTRACT Objective To investigate associations between respiratory capacity, quality of life and cognitive function in elderly individuals. Methods The sample included 386 elderly individuals (232 women). Respiratory capacity assessment was based on maximal expiratory pressure measured at peak expiratory flow. Subjects were classified according to peak expiratory flow values adjusted for sex, age and height of individuals with normal (peak expiratory flow curve <80% and >60%) or reduced (peak expiratory flow curve < 60%) respiratory capacity. The World Health Organization Quality of Life Questionnaire and the Mini-Mental State Examination were used to assess quality of life and cognitive function, respectively. Results Elderly women with reduced respiratory capacity scored lower on the Mini-Mental State Examination (p=0.048) and quality of life questionnaire (p=0.040) compared to those with normal respiratory capacity. These differences were not observed in men (p>0.05). Conclusion Reduced respiratory capacity was associated with poorer quality of life and cognitive function in elderly women. These associations were not observed in elderly men.

RESUMO Objetivo Investigar a associação entre capacidade respiratória, qualidade de vida e função cognitiva em idosos. Métodos A amostra incluiu 386 idosos (232 mulheres). A capacidade respiratória foi avaliada pela pressão expiratória máxima obtida no pico de fluxo expiratório. Com base nos resultados máximos de fluxo expiratório, os indivíduos foram classificados de acordo com o valor previsto para sexo, idade e estatura em capacidade respiratória normal (curva de fluxo expiratório de pico inferior a 80% e superior a 60%) ou capacidade respiratória reduzida (curva de fluxo expiratório de pico menor que 60%). O questionário World Health Organization Quality of Life e o Miniexame do Estado Mental foram utilizados para avaliar a qualidade de vida e a função cognitiva, respectivamente. Resultados Em comparação com mulheres idosas com capacidade respiratória normal, as pessoas com capacidade respiratória reduzida apresentaram escores mais baixos para o Miniexame do Estado Mental (p=0,048) e qualidade de vida (p=0,040). Nos homens, não foram observadas diferenças (p>0,05). Conclusão Capacidade respiratória reduzida foi associada à pior qualidade de vida e à função cognitiva em mulheres idosas. Essas associações não foram observadas em idosos do sexo masculino.

Desfechos tardios de sobreviventes de ensaio clínico randomizado controlado (protocolo ARDSnet vs. Open Lung Approach para o manejo ventilatório da síndrome do desconforto respiratório agudo moderado-grave) / Long-term outcomes in moderate/severe acute respiratory distress syndrome survivors included in a randomized clinical trial (ARDSnet protocol vs. Open Lung Approach)

Apesar da utilização da ventilação mecânica protetora como estratégia para o tratamento da síndrome do desconforto respiratório agudo, ao menos um quarto dos pacientes com essa síndrome ainda apresentam redução na função pulmonar após 6 meses de seguimento. Não se sabe se esta redução está relacionada com a gravidade da síndrome ou associada com a forma de ventilar o paciente. Nosso objetivo neste trabalho foi avaliar a associação entre alterações funcionais e estruturais do pulmão com parâmetros de gravidade clínica e de ventilação mecânica. Foi realizada uma análise secundária dos dados obtidos em estudo randomizado e controlado que incluiu pacientes com síndrome do desconforto respiratório agudo moderada/grave, internados em seis unidades de terapia intensiva em um hospital terciário da cidade de São Paulo. Foram analisados dados de pacientes que tinham ao menos um teste de função pulmonar no seguimento. O teste funcional incluiu a medida da capacidade vital forçada, volumes pulmonares e a capacidade de difusão do monóxido de carbono após 1, 2 e 6 meses de seguimento. Foram considerados variáveis independentes o volume corrente, a pressão de distensão e a pressão positiva ao final da expiração (todos medidos após 24 horas da randomização) e um sistema de classificação de prognóstico (APACHE II), a relação PaO2/FIO2 e a complacência respiratória estática (todos medidos antes da randomização). Também foi realizada tomografia de alta resolução do tórax juntamente com os testes de função pulmonar, e posterior análise quantitativa das imagens. Na avaliação de 6 meses também foi realizado teste de caminhada de 6 minutos e um questionário de qualidade de vida (SF-36). Um total de 21 pacientes realizaram o teste de função pulmonar após 1 mês e 15 pacientes realizaram após 2 e 6 meses de seguimento. A capacidade vital forçada foi relacionada inversamente com a pressão de distensão na avaliação de 1, 2 e 6 meses (p < 0,01). A capacidade de difusão do monóxido de...

Even after lung-protective ventilation had become the standard of care for acute respiratory distress syndrome, about 25% of moderate/severe acute respiratory distress syndrome patients present reduction in lung function at 6 months of follow-up. It is not known whether this reduction is related to the severity of acute respiratory distress syndrome or associated with mechanical ventilation strategy. Our aim was to evaluate the association between the functional impairment and mechanical ventilation. We performed a secondary analysis of data from a randomized controlled trial in acute respiratory distress syndrome that included patients with moderate/severe acute respiratory distress syndrome in six intensive care units at an academic tertiary hospital. Were analyzed data from patients who had at least one pulmonary function test at the follow-up. A pulmonary function test that included forced vital capacity, lung volumes and carbon monoxide diffusion capacity was performed at one, two and six months of follow-up. We considered as independent risk factors tidal volume, driving pressure and positive end expiratory pressure (all measured 24 hours after randomization), and a severity of disease classification system (APACHE II), the PaO2/FIO2 ratio and static respiratory compliance (all measured before randomization). We performed also a high-resolution computed tomography of the lungs in the same time of the pulmonary function test if it was possible with a quantitative analysis. At 6 months after acute respiratory distress syndrome, a six minute walk test and a quality of life questionnaire (short form-36 questionnaire) were performed. A total of 21 patients performed the test after one month and 15 patients performed after 2 and 6 months follow-up. At one, two and six months, forced vital capacity was related to driving pressure (p < 0.01). Carbon monoxide diffusion capacity was related to driving pressure (p < 0.01) and to APACHE II (p < 0.01)...

Relationship Between Patient-Reported Outcomes and Clinical Outcomes in Patients With Morquio A Syndrome

Abstract This cross-sectional analysis assessed the correlation between patient-reported outcomes (PROs) and clinical outcomes in 24 German patients with Morquio A. Clinical outcomes included 6-minute walk test (6MWT), 3-minute stair climb (3MSC) test, and joint range of motion as measures for endurance/mobility, forced vital capacity (FVC) and maximum voluntary ventilation (MVV) as measures for respiratory function, and height as an important manifestation. The PROs included the EuroQoL (EQ) 5D-5L (EQ5D-5L), to measure health-related QoL (HRQoL), and patients' rating of their ability to walk, climb, or breathe. In adults, endurance and pulmonary function measures and height showed strong and statistically significant correlation with the patients' EQ5D-5L (6MWT: R = .884, 3MSC test: R = .852, FVC: R = .815, MVV: R = .825, height: R = .842). The adult patients' rating of their ability to walk and climb also correlated strongly with 6MWT (R = .839) and 3MSC test (R = .700) results. Improvements in these clinical outcomes may be robust surrogate parameters of a better EQ5D-5L/HRQoL in patients with Morquio A.

Percepção de dispneia em repouso e em atividades físicas habituais em diferentes graus de obesidade / Perception of dyspnea at rest and in daily physical activities in varying degrees of obesity

JUSTIFICATIVA E OBJETIVO: Dispneia é uma experiência subjetiva de desconforto respiratório, cujos mecanismos fisiopatológicos e de percepção são complexos. O objetivo deste estudo foi avaliar a percepção de dispneia dos obesos em repouso e em atividades físicas habituais, utilizando três escalas de dispneia, e verificar a influência do peso corporal na percepção de dispneia crônica. MÉTODOS: Estudo transversal, incluindo 140 pacientes com peso normal e sobrepeso (grupo controle) e obesidade graus I, II e III, que foram subdivididos em seis subgrupos. Dispneia crônica foi avaliada utilizando-se descritores de dispneia e percepção de dispneia em repouso e em atividades físicas habituais por meio três escalas de dispneia: Escala Analógica Visual, Escala de Diagrama de Custo de Oxigênio e Medical Research Council modificada. RESULTADOS: Os grupos tiveram distribuição homogênea quanto a gênero, idade, cor da pele, altura, status tabágico e atividade física. O peso corporal médio foi 109,5±30,9kg e o índice de massa corporal de 39,91±10,57kg/m², com diferenças significativas entre os grupos (p<0,001). Nenhum dos pacientes referiu dispneia em repouso em posição sentada, nas três escalas utilizadas. Houve diferenças significativas entre os grupos quanto à percepção de dispneia em atividades físicas habituais, que se intensificaram nos grupos com o índice de massa corporal mais elevada (p<0,0001). CONCLUSÃO: Indivíduos obesos livres de comorbidades que influenciam a percepção de dispneia não demonstram dispneia em repouso; todavia, apresentaram dispneia crônica em atividades físicas habituais da vida diária, que sofre influência do aumento progressivo do peso corporal...

BACKGROUND AND OBJECTIVE: Dyspnea is a subjective experience respiratory distress whose pathophysiological mechanisms and perception are complex. The objective of this study was to evaluate the perception of dyspnea in obese at rest and in habitual physical activities, using three scales of dyspnea, and check the influence of body weight on the perception of chronic dyspnea. METHDOS: Cross-sectional study including 140 patients with normal weight and overweight (control group) and obesity grades I, II and III, which were subdivided into six subgroups. Chronic dyspnea was assessed using descriptors of dyspnea and perception of dyspnea at rest and in daily physical activities through three dyspnea scales: Visual Analog Scale, Oxygen Cost Diagram scale and modified Medical Research Council. RESULTS: The groups were homogeneous distributed according to gender, age, skin color, height, smoking status and physical activity. The average body weight was 109.5±30.9kg and body mass index 39.91±10.57kg/m², with significant differences between groups (p<0.001). None of the patients reported dyspnea at rest in a sitting position according to the three scales used. There were significant differences between the groups regarding the perception of dyspnea in daily physical activities, which were intensified in the groups with higher body mass index (p<0.0001). CONCLUSION: Obese individuals with no comorbidities which can influence the perception of dyspnea had no dyspnea at rest; however, they presented with chronic dyspnea in daily physical activities of daily living, influenced by the progressive increase in body weight...

Diagnosis and treatment of gastric carcinoma combined with severe pulmonary dysfunction in 20 cases / 国际外科学杂志

Objective To summarize the experience of operation on gastric carcinoma combined with severe pulmonary dysfunction and reduce the incidence of postoperative fatality and complications.Methods According to FVC,MVV,FEV1 from high to low grouping,and interfere with ambroxol hydrochloride,doxofylline,budesonide,terbutaline,ipratropium bromide,tiotropium bromide to 20 patients who suffered gastric carcinoma combined with severe pulmonary dysfunction before and after operation,and interfere with different anesthesia methods.Results Postoperative complications occurred in 20 patients within one month,Hydrothorax in 2 cases,pulmonary infection in 2 cases,respiratory failure in 2 cases,acute pulmonary edema in 1 cases,acute pulmonary embolism in 1 case.After active treatment,19 patients cured,1 case died due to acute pulmonary edema.Conclusion The complications rate and risks are high in the gastric carcinoma patients combined with severe pulmonary dysfunction,and strict preoperative and postoperative managements are key to the operation.

Fatores que influenciam a capacidade física de pacientes com doença pulmonar obstrutiva crônica / Factors that influence physical capacity of patients with chronic obstructive pulmonary disease

Este estudo objetivou identificar fatores que influenciam a capacidade física, avaliada por meio da distância percorrida no teste de caminhada de seis minutos (TC6'), de pacientes com doença pulmonar obstrutiva crônica (DPOC). Os fatores testados foram idade, grau de obstrução das vias aéreas (pelo volume expiratório forçado no primeiro segundo (VEF1), resistência da musculatura respiratória (pela ventilação voluntária máxima (VVM) e capacidade máxima ao esforço (medida pela distância percorrida no teste cardiopulmonar limitado por sintomas, TCP). Dezoito pacientes do sexo masculino, com idade média de 69,6±8,4anos e diagnóstico de DPOC classes II e III, foram submetidos ao TC6', ao TCP e à espiromeria. Foram encontradas correlações significativas moderadas entre a distância percorrida no TC6' e o VEF1 (r=0,62), a VVM (r=0,50), e a distância percorrida no TCP (r=0,67), não havendo correlação com a idade. Conclui-se que o grau de obstrução das vias aéreas, a resistência da musculatura respiratória e a capacidade máxima ao esforço influenciam a capacidade física dos pacientes com DPOC classes II e III ao executar uma atividade cotidiana como a caminhada.

The purpose of this study was to verify to what extent certain factors may influence physical capacity (as assessed by the six-minute walk test, 6MWT) of patients with chronic obstructive pulmonary disease (COPD); factors considered were age, forced expiratory volume in one second (FEV1), maximum voluntary ventilation (MVV), and distance covered in the symptom-limited cardiopulmonary exercise test (CET). Subjects were 18 male elderly (mean age 69.6±8.4 years) with II- and III-degree COPD diagnosis, submitted to spirometry and the 6MW and CE tests. Moderate significant correlations were found between distance walked at the 6MWT and FEV1 (r=0.62), MVV (r=0.50), and distance walked in CET (r=0.67); no correlation was found with age. Therefore, it may be said that the degree of airway obstruction, endurance of respiratory muscles, and maximum exertion capacity may influence physical capacity of subjects with II- and III-degree COPD when performing a daily activity such as walking.

Equações para a previsão da potência aeróbia (VO2) de jovens adultos brasileiros / Equations for predicting aerobic power (VO2) of young Brazilian adults

FUNDAMENTO: O VO2 pode ser previsto, com base em parâmetros antropométricos e fisiológicos, para determinadas populações. OBJETIVO: Propor modelos preditivos do VO2 submáximo e máximo para jovens adultos brasileiros. MÉTODOS: Os 137 voluntários (92 homens) foram submetidos ao teste progressivo de esforço máximo (GXT) no ciclo ergômetro (Monark®, Br). Medidas de trocas gasosas e ventilatórias foram realizadas em circuito aberto (Aerosport® TEEM 100, EUA). Em outro grupo, 13 voluntários foram submetidos ao GXT e a um teste de onda quadrada (SWT), para avaliar a validade externa das fórmulas do ACSM, de Neder et al e do nomograma de Åstrand-Ryhming. Adotou-se o delineamento experimental de validação cruzada e o nível de significância de p < 0,05. RESULTADOS: Para homens durante esforços submáximos deduziu-se um modelo matemático, com base na carga de trabalho, massa corporal e idade, que explicou 89 por cento da variação do VO2 com o EPE (erro padrão da estimativa) = 0,33 l.min-1. Para a carga máxima do grupo masculino outro modelo, com as mesmas variáveis, explicou 71 por cento da variação VO2 com EPE = 0,40 l.min-1. Para as mulheres foi possível explicar 93 por cento da variação VO2 com EPE = 0,17 l.min-1, no esforço submáximo e máximo, com apenas uma equação que empregava as mesmas variáveis independentes. CONCLUSÃO: Os modelos derivados no presente estudo demonstraram ser acurados para a previsão do VO2 submáximo e máximo em jovens adultos brasileiros.

BACKGROUND: VO2 may be predicted with base on anthropometric and physiological parameters for determined populations. OBJECTIVE: To propose models for submaximal and maximal VO2 prediction in young Brazilian adults. METHODS: A total of 137 volunteers (92 men) underwent graded maximal exercise test (GXT) in a cycle ergometer (MonarkTM, Br). Gas exchange and respiratory measurements were performed in an open circuit (AerosportTM TEEM 100, USA). In another group, 13 volunteers underwent GXT and a square wave test (SWT) in order to evaluate the external validity of Neder et al's formula, ACSM's formula, and of Åstrand-Ryhming nomogram. The study design chosen was a cross-validation and the significance level was set at p < 0.05. RESULTS: For men during submaximal exercises, a mathematical model was deduced with base on workload, body mass, and age, which explained 89 percent of the VO2 variation, with SEE (standard error of the estimate) = 0.33 l.min-1. For the maximum load in the male group, another model with the same variables explained 71 percent of VO2 variation, with SEE = 0.40 l.min-1. For women, 93 percent of VO2 variation could be explained, with SEE = 0.17 l.min-1, both in submaximal and maximal exercise, with only one equation by use e of the same independent variables. CONCLUSION: The models derived in the present study proved to be accurate to predict submaximal and maximal VO2 in young Brazilian adults.

The impact of obesity on pulmonary function in adult women

INTRODUCTION: Obesity can cause deleterious effects on respiratory function and impair health and quality of life. OBJECTIVE: To evaluate the effects of obesity on the pulmonary function of adult women. METHODS: An obese group, constituted of 20 women between 20 and 35 years old with a BMI of 35 - 49.99 kg/m² who were non-smokers and sedentary and had no lung disease were recruited. The non-obese group consisted of 20 women between 20 and 35 years old who were sedentary and non-smokers and had no lung disease and a body mass index between 18.5 and 24.99 kg/m². Spirometry was performed in all subjects. The statistical analysis consisted of parametric or non-parametric tests, depending on the distribution of each variable, considering p < 0.05 to be statistically significant. RESULTS: The obese group presented a mean age of 25.85 ± 3.89 years and a mean BMI of 41.1 ± 3.46 kg/m², and the non-obese group presented a mean age of 23.9 ± 2.97 years and a mean body mass index of 21.91 ± 1.81 kg/m². There were no significant differences between the obese group and the non-obese group as to the age, vital capacity, tidal volume, forced vital capacity, and forced expiratory volume in one second. However, the obese group presented a greater inspiratory reserve volume (2.44 ± 0.47 L vs. 1.87 ± 0.42 L), a lower expiratory reserve volume (0.52 ± 0.32 L vs. 1.15 ± 0.32 L), and a maximal voluntary ventilation (108.5 ± 13.3 L/min vs. 122.6 ± 19.8 L/min) than the non-obese group, respectively. CONCLUSION: The alterations evidenced in the components of the vital capacity (inspiratory reserve volume and expiratory reserve volume) suggest damage to the chest mechanics caused by obesity. These factors probably contributed to a reduction of the maximal voluntary ventilation.

Differences in Prediction Formulas for the MVV According to the Status of Ventilatory Function / 대한내과학회지

OBJECTIVES: The MVV reflects subjective dyspnea, exercise capacity, postoperative complication. But, the MVV embodies certain disadvantages and is dependent on coordination, endurance and motivation. A timed vital capacity for calculation of an indirect maximal voluntary ventilation is used. We evaluated differences in prediction formulas for the MUV according to the status of ventilatory function. METHODS: Forty-seven normal subjects, 68 patients with obstructive ventilatory impairment, and 23 patients with restrictive ventilatory impairment were studied. The relationships between the MVV and Flow or time parameters in forced expiratory volume and flow volume curves were compared among normal subjects and patients with obstructive or restrictive ventilatory impairment. RESULTS: 1) High correlation coefficients(R>or=0.87) were found between the FEV0.5, 0.75, 1 and the MVV in 47 normal subjects and 91 patients with ventilatory impairment. 2) The MVV can be conveniently estimated from the FEV1 values. The following regression formulas for the prediction of the MVV were obtained. Normal: MVV=44.01 X FEV1-21.09(r(2)=0.771, SEE=11.085) Obstructive ventilatory impairment: MVV=38.34 X FEV1-4.58(r(2)0.812, SEE=4.816) Restrictive ventilatory impairment: MVV=45.20 X FEV1-3.80(r(2)=0.899, SEE=6.929). 3) There were significant differences in prediction formulas for the MVV obtained by FEV1 between each group (P<0.05). CONCLUSION: These results suggest that different prediction formulas for the MVV, by multiplying the FEV1 by a constant, are respectively required in normal subjects and patients with obstructive or restrictive ventilatory impairment.